Web应用的UML协作图建模与形式化规格说明

针对Web应用的特点,从整体功能层面和交互行为层面用UML协作图构建了Web应用模型,以便精确、有效地描述参与协作对象间的结构关系和交互行为,保证在利用UML形式的规格说明推导测试用例时所需的语义信息.研究了运用Object-Z语言来形式化描述Web应用模型,提出了相应的转换规则.设计了形式化规格说明自动化生成的工具(UMLTOZ)中的主要相关类库.     

用带时钟变量的线性时态逻辑扩充Object-Z*

Object-Z是形式规格说明语言Z的面向对象扩充,适合描述大型面向对象软件规格说明,但它不能很好地描述连续性实时变量和时间限制。线性时态逻辑能够描述实时系统,但不能很好地处理连续时间关系,也不能很好地模块化描述形式规格说明。首先用时钟变量扩充线性时态逻辑,接着提出了一个方法——用带时钟变量的时态逻辑(LTLC)来扩充Object-Z。用LTLC扩充的Object-Z是一个模块化规格说明语言,是Object-Z语法和语义的最小扩充,其最大优点在于它能方便地描述和验证复杂的实时软件规格说明。     

带OCL约束条件的类图到object—Z规格说明的转换

如何提高软件的可靠性是目前软件研究领域的一个热点。将形式化方法和主流的软件开发方法相结合是一个可行的方法。本文研究UML语言和Object-Z语言相结合的方法，为主流的软件开发人员所使用的图形化规格说明技术与形式方法提供的精确的分析和验证技术架起了一座桥梁。本文定义如何将带0CL约束条件的类图转换到Object-Z规格说明的方法。这样不仅可以通过支持Object-Z语言的工具采对UML语言描述的系统性质进行验证和确认，而且能够帮助规格说明人员方便地构造Object-Z规格说明。     

一个Object-Z规格说明的证明责任产生器

定理证明是一种形式化验证技术,也是形式化方法的重要组成部分,它能从形式规格说明中推理出应具备的性质与属性,从而可以对规格说明进行形式验证。Object-Z是形式规格说明语言Z的面向对象扩充,基于集合论与数理逻辑,具有严密的逻辑性,适合于精确地描述大型软件系统,并且可以对其形式规格说明进行推理。设计一个证明责任产生器,从Object-Z形式规格说明出发,按照相关规则自动抽取相应的证明责任,这些证明责任可以直接输入到已有的定理证明器Z/EVES中进行证明之。证明责任产生器起着Object-Z规格说明编辑器与证明器Z/EVES之间的桥梁作用,方便于Object-Z形式规格说明的验证。     

面向对象软件的形式规格说明技术

本文介绍四种面向对象形式规格语言。Object-Z是Z语言的一种扩充,可用于面向对象软件需求规格的形式说明。为研究软件维护和逆向工程,提出了Z~(++),是Z的另一种扩充,其中引入了过程式描述机制。COLD-K是基于代数规格说明技术的面向对象软件设计语言,是一种核心语言,可设计面向用户的形式规格语言,JOOSL是基于COLD-K和Z语言的一种面向对象设计语言,可用于软件自动化的研究。     

产生证明责任验证Object—Z规格说明的行为子类型继承

Object-Z是形式规格说明语言Z的面向对象扩充,具有面向对象特点,适合描述大型面向对象软件规格说明.行为子类型继承是一种子类型继承,子类型对象拥有其超类对象的行为与属性,如果行为子类型对象替代其超类型对象时,运行时不会出错,经过验证过的形式规格说明不必再验证.本文对Object-Z定义了行为子类型继承,尤其我们系统地提出一个实现行为子类型继承和对规格说明产生相关证明责任的方法,其中这些证明责任可以判定形式规格说明是否按照其行为子类型方法进行开发的.最后,充分利用定理证明器Z/EVES来分析与验证所产生的证明责任.     

Object—Z规格说明的SQL动画模拟

软件规格说明的确认在软件开发阶段占有举足轻重的地位。形式规格说明的动画模拟技术是一种规格说明的确认方法。本文研究了Obiect-Z规格说明的SQL动画模拟方法，设计了从Object-Z到SQL的转换规则，并提出了模块封装的思想，即用存储过程表示类、对象和模式等模块，用户通过调用执行存储过程确认规格说明是否满足其需求。     

基于形式规格说明和分类树方法生成软件测试用例

介绍了一种基于形式规格说明和分类树方法生成软件测试用例的方法。由软件的形式规格说明构造分类树，再把由分类树方法得到的测试用例转化为析取范式，进一步精炼测试用例。并通过一个实例说明测试用例的设计过程。     

Object-Z规格到实现机制探讨

形式化规格是保证所设计的系统具有较高的可信度和正确性的重要途径,它涉及软件生命周期的各个阶段。从形式化规格到软件编码是软件开发中的一个关键环节。在分析了规格化和高级语言之间的内在关系的基础上,概括了基于Object-Z规格到Java实现的几条转换机制,并运用案例研究来说明这些机制。     

基于GCL语言的测试用例生成方法

提出一种基于GCL语言生成程序测试用例的形式化方法.程序的语义为测试用例的生成提供了基本框架,而由Hoare等人提供的规则保证了用例的正确性.作者的这种方法可被认为是一种严格的,自动生成测试用例的方法.这种方法的优点在于:所获得的测试用例都是可行的,在测试用例生成过程中可以避免状态爆炸问题,而且该方法可以延拓到任何目标语言.据此开发了一个基于Haskell语言的原型工具来支持作者的方法.     

Object-Z: A specification language advocated for the description of standards

The importance of formalising the specification of standards has been recognised for a number of years. This paper advocates the use of the formal specification language Object-Z in the definition of standards. Object-Z is an extension to the Z language specifically to facilitate specification in an object-oriented style. First, the syntax and semantics of Object-Z are described informally. Then the use of Object-Z in formalising standards is demonstrated by presenting a case study based on the ODP Trader. Finally, a formal semantics is introduced that suggests an approach to the standardisation of Object-Z itself. Because standards are typically large complex systems, the extra structuring afforded by the Object-Z class construct and operation expressions enables the various hierarchical relationships and the communication between objects in a system to be succinctly specified.     

Specification, Refinement and Verification of Concurrent Systems—An Integration of Object-Z and CSP

This paper presents a method of formally specifying, refining and verifying concurrent systems which uses the object-oriented state-based specification language Object-Z together with the process algebra CSP. Object-Z provides a convenient way of modelling complex data structures needed to define the component processes of such systems, and CSP enables the concise specification of process interactions. The basis of the integration is a semantics of Object-Z classes identical to that of CSP processes. This allows classes specified in Object-Z to be used directly within the CSP part of the specification.In addition to specification, we also discuss refinement and verification in this model. The common semantic basis enables a unified method of refinement to be used, based upon CSP refinement. To enable state-based techniques to be used for the Object-Z components of a specification we develop state-based refinement relations which are sound and complete with respect to CSP refinement. In addition, a verification method for static and dynamic properties is presented. The method allows us to verify properties of the CSP system specification in terms of its component Object-Z classes by using the laws of the CSP operators together with the logic for Object-Z.     

An Introduction to Real-Time Object-Z

This paper presents Real-Time Object-Z: an integration of the object-oriented, state-based specification language Object-Z with the timed trace notation of the timed refinement calculus. This integration provides a method of formally specifying and refining systems involving continuous variables and real-time constraints. The basis of the integration is a mapping of the existing Object-Z history semantics to timed traces. Received September 2000 / Accepted in revised form June 2001     

XQuery语言的形式化语义

XQuery语言用于查询XML文档。目前，该语言规范还是W3C的工作草稿。语言的形式化语义有助于语言的标准化，本文通过重用XML家族语言通用语义构件的方法，形式化建模XQuery语言的语义，语义的描述采用Object—Z规范语言。这种面向对象的语义描述不仅具有简洁性、可扩展性和可组合性，而且有助于规范之间的一致性和协调性。     

Structural Refinement of Systems Specified in Object-Z and CSP

This paper is concerned with methods for refinement of specifications written using a combination of Object-Z and CSP. Such a combination has proved to be a suitable vehicle for specifying complex systems which involve state and behaviour, and several proposals exist for integrating these two languages. The basis of the integration in this paper is a semantics of Object-Z classes identical to CSP processes. This allows classes specified in Object-Z to be combined using CSP operators. It has been shown that this semantic model allows state-based refinement relations to be used on the Object-Z components in an integrated Object-Z/CSP specification. However, the current refinement methodology does not allow the structure of a specification to be changed in a refinement, whereas a full methodology would, for example, allow concurrency to be introduced during the development life-cycle. In this paper, we tackle these concerns and discuss refinements of specifications written using Object-Z and CSP where we change the structure of the specification when performing the refinement. In particular, we develop a set of structural simulation rules which allow single components to be refined to more complex specifications involving CSP operators. The soundness of these rules is verified against the common semantic model and they are illustrated via a number of examples.     

基于Object-Z的XPath形式化语义

本文描述了XPath语言的形式化语义。一个统一的面向对象的语义视角用于建模所有XPath语言构造。语义的表示采用形式化规范语言Object-Z的符号系统。这种高度结构化的语义模型具有简洁、可组合性和可复用性的特点。     

A fully abstract semantics of classes for Object-Z

This paper presents a fully abstract semantics of classes for the object oriented formal specification language Object-Z. Such a semantics includes no unnecessary syntactic details and, hence, describes a class in terms of the external behaviour of its objects only. The semantics, based on an extension of existing process models, defines a notion of behavioural equivalence which is stronger than that of CSP and weaker than that of CCS.     

应用代数规约和数据变异策略测试类

在应用基于代数规约测试类时,虽然可以有效解决测试数据生成和测试结果判断这两个测试难题,但是,因为该方法常常随机生成测试数据,会导致对于同一待测试类两次测试会得到不同的测试效果。为克服这个缺陷,提出应用数据变异方法,对已生成的测试用例进行变异。变异测试实验表明：该方法能够有效地改善代数测试方法的测试效果。     

基于Z规格说明的软件测试用例自动生成

提出了一种基于Ｚ规格说明的软件测试用例自动生成方法,通过对软件Ｚ规格说明的分析,找出描述软件输入、输出约束的线性谓词,经过经性谓词转换,线性谓词到线性不等式组的转换,找出区域边界顶点和边界附近的测试点等过程自动生成测试用例。同时还介绍了基于Ｚ规格说明的软件测试用例自动生成方法的实例,并通过一个实例进一步加以说明。